1. Field of the Invention
This invention relates to a method wherein a large number of kinds of cells existent in a smeared cell sample are classified by utilizing characteristic parameters on the shape information and density information of the cells. More particularly, it relates to a method of compensating for the variances of the characteristic parameters among cell samples, and a method of calculating secondary characteristic parameters.
2. Description of the Prior Art
In recent years, as seen in an automated cyto-screening system, an automated leukocyte analyzer etc., it has been vigorously carried out that characteristics of the shapes and densities of cells are automatically detected with the procedure of pattern recognition, thereby to classify the cells precisely and speedily.
In these systems, a good preparation of a cell sample is one of essential points for enhancing the accuracy of the classification of cells. The process of preparing the cell sample is generally divided into a smearing step and a staining step. It is impossible to subject all the cell samples to the same smearing condition and staining condition. Therefore, variances occur in shape and density (color) characteristics among the cell samples prepared. In the smearing step, drying after smearing is included. If the drying time becomes long, the size (area and peripheral length) of the cell existent in the cell sample will decrease. In the staining step, the color density of the cell existent in the cell sample will vary in dependence on the amount of a staining matter for staining, the staining time, the extent of washing after the staining, etc. It is obvious that such variances of the shape and density (color) characteristics among the cell samples degrade the accuracy of recognition or classification in the system as referred to above.